Pipe indenting machine



July 19, 1966 o. OECKL 3,261,190

PIPE INDENTING MACHINE Filed Oct. 4, 1963 fil' O \9 E O I ,/4 1 2 /6 l fl 7 g /9 z E 2 L 5 b J n 5 W L /Q .1 I U K S/Qv 1/ INVENTOR g I W ATTOZQEYJ United States Patent 4 Claims. (c1. 72-7 This invention is directed to a pipe bending machine and, in particular, to an automatic machine for indenting, grooving, fluting or otherwise shaping a pipe.

Automatic pipe bending machines exist in which the feeding, working and removal of the pipe is accomplished by precision movements of the arbor, the bending assembly and so forth. Recently fully automatic machines have been made in which a rotating chuck holds the pipe so that the pipe can be turned after each bending operation. The chuck is rotated by means of cams which must be changed for different types of work. Such machines have the disadvantage that a great deal of time is consumed in adjusting the machine.

For example, the following steps are required to change the machine from one bending shape to another bending shape for a different pipe:

First, the longitudinal bearing surfaces must be re-set, then the bearing surfaces for the alignment of the bending element must be adjusted, and finally the cams for positioning the pipe-holding chuck have to be set.

Thus, if there are ten new bearing surfaces for each of the above three steps, a pipe receiving ten bends will require a total of thirty machine adjustments. This takes anywhere from one to three days to set up the machine because test pipe bending runs and corrections are usually necessary in making the final adjustments. Moreover, the adjusting of the machine requires the use of highly skilled labor.

Consequently, these automatic pipe bending machines are suitable only for mass production and are not at all suited [for shops which produce a large variety of pipe shapes daily as the latter requires a large stock of master pipes which are used to adjust the machine with the aforesaid large expenditure of time.

The object of this invention is to produce an automatic pipe bending machine which can be quickly set up for a pipe of any given shape with a very low expenditure of time.

In general, this and other objects of the invention are obtained by constructing a machine having a frame with an arbor holding block at one end and a pipe bending assembly at the other end, and a slidable carriage carrying a pipe chuck movably mounted between the lock and the assembly. According to this invention, the longitudinal movement and rotation of the chuck are cont-rolled by a programming reading means movable with the carriage and which reads a program recorded on a tape wound upon reels.

The program is recorded on the tape in the form of a series of holes or rows of contacts, one of which is used for each definite movement of the machine. These recordings can be read off by contact devices or photoelectric cells. There are as many holes or contacts as there are movements to be executed by the machine. For example, the turning of the bending element, forward movement of the sliding carriage, rotation of the chuck either clockwise or counterclockwise, forward and backward movement of the arbor, fast and slow movement of the carriage, and so forth are separately recorded on the tape. The machine does not need and does not use any physically engaging surfaces for the longitudinal movement of the carriage and the turning of the bending element. In order to change over from one pipe shape to another requires only a winding of the tape so that a different recorded program is brought into the range of the program reading means. If the length of the tape is at least as long as that of the pipe, then the recorded program on the tape can have the same scale as the pipe and will increase the precision of the work performed. The tape is programmed from a master pipe which is then no longer needed for the operation of the machine.

The angular position of the pipe holding chuck clockwise or counterclockwise is also determined by the distance between the recorded markings on a specific portion of the tape, and in which the straight portion of the pipe which is always present between two pipe indentations is used as far as time is concerned to start the drive for rotating the chuck.

The means by which the objects of the invention are obtained are disclosed more fully with reference to the accompanying drawings in which:

FIGURE 1 is a top .plan view of the machine partly shown in section; and

FIGURE 2 is a cross-sectional view taken on the line 22 of FIGURE 1.

As is usual in machines of this type, the machine frame 1 has at one end a pipe bending assembly 2 and at the other end the housing block 3 for a piston used to move arbor 4. A mandrel 5 is mounted on the free end of arbor 4. The bending assembly 2 includes clamping jaw 6.

Carriage 7 is slidably mounted on frame 1 and driven by motor 8 which rotates threaded shaft 9. The workpiece, that is the pipe 4a, is held in the rotatable chuck 10 carried on carriage 7. This chuck is rotated or turned ttrom one angular position to another by means of the motor 11.

On .the side of frame 1 are mounted the reels 12 on which the program tape 13 is wound. The recorded pro- (gram on the tape is in the form of holes or contacts arranged in rows 14 to 19, inclusive. Each one of the recorded marks takes care of one definite function of the machine. The program is transferred from the tape to the various drives by means of the reading head 20 attached to carriage 7. The zero or starting position of the chuck 10 is represented by the point 21, FIGURE 2.

The machine operates as follows:

Pipe 4a is first slipped over arbor 4 and secured in chuck 10 which is in its zero position. The carriage is then started from its position adjacent housing 3 by energizing motor 8 and turning shaft 9. The carriage then receives, for example, from row 14 on tape 13 a command to stop and then pipe 411 is introduced into bending assembly 2 by a command from row 15.

The sliding carriage 7 then moves forward again, and at the same time the bending assembly 2 is put into rotation until such time as a further command from row 14 stops carriage 7 as well as bending assembly 2. At this time, the desired degree of bending or indenting the pipe has been accomplished, and the arbor 4 is retracted to pull back the mandrel 5' so that the pipe 4a in bending assembly 2 can be released. The command for the arbor 4 is taken from row 16 on the tape.

Carriage 7 is then further moved to produce other operations as directed from the program recorded on tape 13. If circumferen-tially spaced indentations are to be made on the pipe, then while carriage 7 is moving, a command from row 17 or 18 effects a rotation of chuck 10 clockwise or counterclockwise. Thus the chuck is rotated a definite amount by the motor 11 during the travel of carriage 7 over a pre-determined distance. When this rotation has been achieved, the carriage 7 momentarily stops, pipe 4a is inserted into assembly 2 and the process of bending again started as described.

ice

Other programs can be recorded on tape 13, for example, row 19 is programmed to accelerate the movement 10f carriage 7 when a long stretch of straight pipe lies between .two indentations.

Having now described the means by which the objects of the invention are obtained,

I claim:

1. In combination with a pipe bending machine having an arbor holding block mounted on one end of a frame, a pipe bending assembly mounted on the opposite end of the frame, and a carriage carrying a rotatable chuck slidably mounted on said frame between said block and said assembly, program reading means attached to and movable along with said carriage for actuating said carr-iage and said chuck, and replaceable stationary recorded program means extending the entire length of said frame and readable by said recording means.

2. In the combination of claim 1, said recorded program means comprising a tape having a program recorded thereon and stretched between reels.

References Cited by the Examiner UNITED STATES PATENTS 8/1964 Hill 72-7 OTHER REFERENCES Tube Bending Controlled by Tape, The Iron Age, vol. 185, No. 3, January 21, 1960.

CHARLES W. LANHAM, Primary Examiner.

R. D. GREFE, Assistant Examiner. 

1. IN COMBINATION WITH A PIPE BENDING MACHINE HAING AN ARBOR HOLDING BLOCK MOUNTED ON ONE END OF A FRAME, A PIPE BENDING ASSEMBLY MOUNTED ON THE OPPOSITE END OF THE FRAME, AND A CARRIAGE CARRYING A ROTATABLE CHUCK SLIDABLY MOUNTED ON SAID FRAME BETWEEN SAID LOCK AND SAID ASSEMBLY, PROGRAM READING MEANS ATTACHED TO AND MOVABLE ALONG WITH SAID CARRIAGE FOR ACTUATING SAID CARRIAGE AND SAID CHUCK, AND REPLACEABLE STATIONARY RECORDED PROGRAM MEANS EXTENDING THE ENTIRE LENGTH OF SAID FRAME AND READABLE BY SAID RECORDING MEANS. 